- From: Levantovsky, Vladimir <Vladimir.Levantovsky@MonotypeImaging.com>
- Date: Fri, 7 May 2010 14:35:06 -0400
- To: Tab Atkins Jr. <jackalmage@gmail.com>
- CC: Matt Colyer <matt@typekit.com>, Erik van Blokland <erik@letterror.com>, "www-font@w3.org" <www-font@w3.org>
On Friday, May 07, 2010 12:08 PM Tab Atkins Jr. wrote: > > On Fri, May 7, 2010 at 6:59 AM, Levantovsky, Vladimir wrote: > > Sorry for a delayed response. The reason I proposed to consider > adding > > checksum is because the WOFF file contains extended and private > metadata > > fields that are currently can be easily discarded – one can simply > cut them, > > zero-out related offset/length values in the WOFF header and modify > the WOFF > > length. I realize that adding checksum isn’t going to be a strong > protection > > against willful modifications, the same could be done with the > checksum > > present, but it would require a bit of an effort (to write the code > to > > recalculate the checksum). > > I believe that, by the time people are reaching into the file to cut > out tables and modify several values, recalculating a checksum is > trivial. The operations and abilities required to do so are basically > the same. > Well, the key difference here is that I can discard metadata fields and zero-out their respective offset/length values using any HEX editor with no efforts. Recalculating a checksum does require writing a piece of code. Regards, Vlad
Received on Friday, 7 May 2010 18:34:25 UTC